Lighting device



Jan. 2, 1940. c NOE 2,185,694

LIGHTING DEVICE Filed Jan. 17, 1958 INVENTOR ,4, ATTORNEYS Patented Jan.2, 1940 PATENT OFFICE LIGHTING DEVICE Harold C. Noe, Nutley, N. J.,assignor, by mesne assignments, to Holophane Company, Inc.,-New York, N.Y., a corporation of Delaware Application January '17, 1938, Serial No.185,256 Claims. (c1. 240'-81) This invention relates tolighting devicesand particularly, to desk lamps and similar constructions serving toproduce a diffused but intense illumination over an area beneath andadjacent 5 the device. I v 1 Desk lamps and similar devices asheretofore constructed have served to direct light downward onto an areaadjacent and beneath the lamp shade and to prevent light from radiatinghori zontally from the device. Such devices as presently usedcommercially are usually of one of the following types: wherein there isprovided a shade or the like having a reflecting surface or a separatereflector secured thereto for reflecting the light emanating from thelight source and directing it upon the area or object that it is desiredto illuminate;

(2) the semi-indirect lighting type wherein part of the light rays arereflected and part are radiated directly from the light source upon thearea or object to be illuminated; and (3) the diifusing bowl typewherein all or a part, of the light the source oflight is thustransmitted directly to the shade with the result that the shade becomesheated and in some instances sufficiently hot to cause a painful burnwhen touched. This isparticularly' true when the metal shade'reflectoris used with a lamp of the diffusing bowl type since in such lamps asheretofore constructed it is necessary to use a relatively powerfullight source in order to obtain the desired uniform intenseillumination. v

In accordance with the present invention this objection to constructionsof the prior art is overcome by providing a reflector and shade whichare spaced apart so that heat from the lightsourceand from the reflectoris not transmitted directly to the shade. to lamps of the diffusing bowltype, the present invention produces the further advantage that theefficiency of the lamp is markedly increased as compared with theearlier lamps employing the diifusing bowl principle and at the sametime eliminates the objectionable heating of the shade.

These and other advantages and features of the invention will appearfrom the following description thereof, in which reference is made toCJI (1) Indirect lighting type,

minimum of loss.

tense illumination is obtained without producing In its application thefigure of the drawing which is a vertical sectional View of a lightingdevice embodying the present invention with parts of the constructionillustrated in elevation.

In that form of the invention illustrated the device embodies avertically extending support 2 having asocket 4 for receiving a sourceof light such as the light bulb 6 which extends upwardly from thesupport. The support is provided with an outer shell 8, the upperportion of which is formed with a flange ll] for receiving andsupporting a light diffusing bowl l2. The bowl may be made of anysuitable light diffusing glass or similar material. Advantageously, itmay be made, as shown, of transparent prismatic glass formed withannularly extending prisms M on the outer surface thereof, and radiallyextending prisms IS on the inner surface thereof, such as those shownand described in the patent to Dorey No. 1,699,100. Light emanating fromthe light source 6 and impinging upon the walls of the bowl is diffusedin passing therethrough with a In this way, diffused but ina glare onobjects located adjacent the device.

The bowl is secured in place on the flange I0 by means of screws l8 orthe like which enter I a recess 20 about the lower portion of the bowl.The upper marginal rim of the bowl I2 is formed with an enlarged portion22 havingan upwardly extending annular ridge 24 for receiving andpositioning a reflector 26. The reflector may be formed of aluminum orother suitable material, and is provided with a highly polished innerreflectingsurface 28 for directing light downwardly through the lightdiffusing bowl l2 and onto the surface beneath and adjacent the lightingdevice. With this construction, light from thesource 6 passes eitherdirectly through the light diffusing bowl l2 onto the surface to beilluminated as indicated bythe arrows 30, or is reflected downward fromthe highly polished surface 28 through the light diffusing bowl asindicated by the arrows 32. Thus, a large part of the light from thesource 6 falling on the surface to be illuminated is direct but diffusedlight. Moreover, all of the light, both direct and reflected, passesthrough the light diffusing bowl l2. Therefore, a highly polishedreflecting surface may be used above the light bulb without producing aglare on the objects illuminated. The reflector, because it is highlypolished, also serves to reduce reflection losses and to diminish theabsorption of heat by the reflector.

A light shade 34 formed of metal or other material is provided with aridge 3B which engages the outer marginal portion 38 of the rim 22 onthe light diifusing bowl. The construction of the rim 22 on the bowl andthe ridge 36 on the shade 34 is such as to hold the shade in spacedrelation with respect to the reflector 25 so that there is no contactbetween the reflector and the shade. Thusboth of these elements aresupported independently by the bowl and are held out of contact witheach other. The top id of the shade extends over the reflector 26,"

leaving an air space 42 between the reflector-and the top of the shade.

Since the reflector 28 is highly polished and reflects the light rayswith very little absorption of heat and the air in the air space is avery poor conductor of heat, the shade remains relatively ccol even whenthe device is used for long periods of time.

The lower portion of the shade 3t extends outward and.- downward'aboutthe bowl it with the lower edge i l thereof in line with or below thelower exposed portion of the bowl, so that light cannotradiate outwardhorizontally from the bowl beyond the margin of the shade, but isdirected downwardly onto the area below and adjacent the lightingdevice.

The inner surface 43 of the outwardly and downwardly extending portionof the shade is constructedor provided with a reflecting surface,preferably non-polished and adapted further to difluse and reflect lightfalling thereon and to direct the light downward onto the area below andadjacent the device without producing objectionable glare. An aluminumpainted or spray coated metal surface serves the purpose.

With this construction objectionable heating of the shade isavoided'while providing intense but diflused lighting throughout thearea adjacent and below the device. Moreover, the desired illuminationis obtained without excessive reflection losses so that a relativelysmall light bulb or other light source and; one which produces butlittle heat may be employed without correspondingly reducing theillumination provided.

It will be apparent that the form and construction of the lightdifiusing bowl [2 may be varied considerably, particularly when adaptingthe invention for use in lighting devices diflering in design andarrangement from that illustrated. It will also be evident that othertypes of support and other forms of reflector and shade may be used toproduce various lighting eiTects as desired. Moreover, the meansprovided for mounting the shade and reflector independently also may bevaried as desired without departing from the spirit of the invention. Itis also to be un-' derstood that the advantages of increased efliciencyof lighting with elimination of overheating of the shade may be obtainedby applying the spaced reflector and shade elements in lamps of thedirect and semi-direct lighting types that do not also employ thedifiusing bowl principle. It will be understood from the above thattheform of lighting device shown in the drawing and herein described isintended to be representative of an embodiment of the invention and isnot intended to limit the scope thereof.

an annular domed reflector extending over they light source and fittingthe top of the bowl and having a highly polished inn'er reflectingsurface formed to reflect light downwardly through said light diffusingbowl onto an area adjacent said device, and a shade covering thereflector and supported-in spaced relation with respect to saidreflector to form an air space, the shade having an annular skirtextending outwardly and downwardly about the bowl and formed to reflectthe light radiating laterally from the bowl downwardly onto an areaadjacent said device. a

2. In a lighting device having a support, alight source carried by thesupport,a light difiusingbowl extending upward about the sides of saidlight source, said bowl having an upper marginal rim, j a domedreflector supported on said and serving to reflect light radiated fromsaid light;

source downwardly and outwardly throughsaid diffusing bowl, and a domedcovering means sup ported on said rim above and in spaced relation tosaid reflector and defining a heat insulating air space therebetween.

3. A desk lamp of a height to be normally below 30' eye level andcomprising a support, alight source carried by the supportya lightdiffusing bowl around the source. and a combined cover and screencomprising a central opaque bulged re- .flector detachably secured;above the bowl and thelight source and resting on top of the bowl toreflect light back into the bowl, a light screen extending downwardlyand outwardly from the top of the bowl to substantially the bottomof thebowl to screen the bowl at angles above the ho-ri- I zontal, and havinga wide diameter at the bottom to permit said directed light to escape,and a central domed element above the reflector and vertically spacedfrom it to provide an air space therebetween.

4. A desk lamp of a height to be normally below eye level and comprisinga support, a light source carried by the support, a light diffusing bowlaround the source and a combined cover andfl screen comprisinga centralopaque bulged reflector detachably secured above the bowl and the lightsource and resting on top of the bowl to;

reflect light back into the bowl, a light "screen; extending downwardlyand outwardly from the top of the bowl to substantially the bottom ofthe bowl to screen the bowl at angles above. the

horizontal, and having a wide diameter at the bottom to permit saiddirected light to escape,

and a central domed element above .the reflector and vertically spacedfrom it to provide an air'" space therebetweem'the top of the bowlengaging the edge of the reflector and-the domed element and screen toalign them and keepthe edge of the reflector out of contact with thedomed element.

5. A desk lamp such as claimed in claim 3;

wherein the central domed element and the screen are integral.

HAROLD C. NOE.

